Download Relationships between organisms

Competitive Relationships
LifeSci Unit 5.12
Attendance link: http://goo.gl/forms/dJ9iQzBOQN
Expectations
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Required Class Connects
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Be active and participate in class.
Be respectful to your classmates
Be positive in the chat box and use it correctly.
Have a working microphone!
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Tuesday, Wednesday, & Thursday
10:30-11:30 am
You will need it during the lessons and break out rooms.
If you have a question, please place it in the chat box and repost it if I
don’t see it.
Objectives
• Give examples of competition in specific
environments (freshwater, ocean, forest,
desert, grassland, mountain region, etc.).
• Describe the interaction of predators and prey
in a specific area and relate the interaction to
competition for resources.
Connections between organisms
• All living things on the earth
are connected in some way.
• This unit we will study these
relationships:
– Producer/consumer/decomposer
– Predator/Prey
– Competition
Competition – two species share a requirement for a
limited resource  reduces fitness of one or both species
Producer/consumer/decomposer
• We’ve already learned
that a producer is able
to use the sun’s energy
to make food.
• We’ve also learned that
a consumer has to get
food by eating
producers (herbivore)
or other consumers
(carnivore) or both,
(omnivore).
Producer/consumer/decomposer
• Producers (autotrophs)
capture the energy that
all other organisms rely
on to survive.
• Without producers, the
sun’s energy couldn’t be
used by living things.
Producer/consumer/decomposer
• A decomposer is an
organism that breaks
down waste and dead
organisms.
• Decomposers help to
recycle nutrients.
• Without decomposers,
dead things would pile
up, and nutrients would
run out.
Consumers - Predator/Prey
• An organism that kills
and eats another
organism for food is
called a predator.
• An organism that gets
killed and eaten by a
predator is called the
prey.
Predator/Prey
• Predator populations rise
and fall in relation to the
prey they eat.
– (If there is a decrease in
the amount of prey, there
will soon be a decrease in
the amount of predators).
– (If there is an increase in
the amount of prey, there
will soon be an increase in
the amount of predators).
Predation
• Predation is any interaction between two
organisms in which one organism (the
predator) consumes all or part of another
organism (the prey).
Predation – one species feeds on another  enhances
fitness of predator but reduces fitness of prey
herbivory is a form of
predation
Predation
one eats another (Herbivores eat plants.
Carnivores eats animals.)
Competition
• Competition occurs
when 2 or more
organisms are both
trying to use the same
limited resource.
Competition
• Competition in an interaction between two
organisms that are using the same limited
resource.
• Competition can be within the same
species (intraspecific) or between different
species (interspecific).
Competition
• Competition could
occur between
producers or consumers
• Competition might
occur between
organisms of the same
species, or different
species.
Competition
• Competition might
occur because of
limited:
–
–
–
–
–
Food
Space
Sunlight
Mates
Or any other limited
resource
What does head-butting in bighorn
sheep illustrate?
A. Competition among members of the same
species
B. Competition among members of different
species.
C. Predator-prey relationships in bighorn sheep.
D. Predation of members of the same species.
An example of competition
between members of the same
population in a community is a
male lion chases after another lion
that invaded its territory.
Herbivore-Plant Interactions
• An herbivore
grazing on a
plant is another
example of
predation.
• Usually, only
part of the prey
is eaten by the
predator.
•
Photo Credit: Rhett A. Butler @
mongabay.com
Herbivore-Plant Interaction:
Manatee Grazing on Aquatic Plants
Limiting factor
• The resource that runs
out when a population
reaches its carrying
capacity is called the
limiting factor.
• Limiting factors lead to
competition between
organisms.
Under which condition is competition
among lions least likely?
A.
B.
C.
D.
When there are fewer producers in that area.
When there is a large zebra population.
When there are large number of lions.
When there is abundant rainfall in the area.
Which interaction is most likely to
result in the most competition among
the organisms?
A. Lions and vultures eat the remains left after a
lion kill.
B. Sagebrush and cacti obtain light in the
desert.
C. Grasshoppers and caterpillars eat oak leaves.
D. Producers and scavengers eat deer carcasses.
Example: Interspecific Competition
• Two species of barnacles on rocky coasts
often compete for space.
• The smaller species (Chthamalus) is
unable to compete as well as the larger
species (Balanus).
• However, Chthamalus can survive drying
better than Balanus, so it can live higher
up on the rocks.
Example: Interspecific Competition
• A small
Chthamalus
barnacle is
circled in red.
• A large
Balanus
barnacle is
circled in blue.
•
Photo Credit: Department of the Interior
Experiment: Interspecific Competition
• In Scotland,
Joseph Connell
studied
interspecific
competition in
these two
barnacles.
• In places where
both barnacles
were present, he
removed the
Balanus
barnacles from
the rocks.
Experiment: Interspecific Competition
• When Balanus
barnacles were
removed, the
Chthamalus
barnacles moved
down into the
vacant area.
• This showed that
Balanus was
outcompeting
Chthamalus in
the lower zone.
Experiment: Interspecific Competition
• At other sites where both barnacles were
present, he removed Chthamalus
barnacles from the rocks.
• The vacant areas remained unoccupied.
• This showed that Balanus was not able to
survive in the upper zone.
Experiment: Interspecific Competition
• The distribution of these two barnacles
is a result of a combination of:
– Interspecific competition: Chthamalus is
excluded from the lower zone by Balanus
– Adaptations to dryness and heat: Balanus
cannot survive in the upper zone but
Chthamalus can
Why are ecological interactions important?
Interactions can affect distribution and abundance.
Interactions can influence evolution.
Think about how the following interactions can affect
distribution, abundance, and evolution.
Which of these is likely to result in
the most competition?
A. Organisms that live in different ecosystems.
B. Organisms that live in the same area.
C. Organisms that are classified in the same
phylum.
D. Organisms that use the same resource.
Parasitism
One organism, usually physically smaller of the
two (the parasite) benefits and the other (the
host) is harmed
Parasitism – one species feeds on another  enhances
fitness of parasite but reduces fitness of host
Ticks and fleas that live in a host
animal's fur bite the animal and drink
its blood are parasites.
Insects such as mosquitoes feeding on
a host are parasites.
Vines such as Kudzu growing on Trees
Tomato Hornworm with Wasp Eggs
Tapeworm or Hookworms living in Host's
Gut
The roots of the Owl Clover are partly
parasitic on the roots of other desert
wildflowers.
Competition, Predation, and Symbiosis (3:19 minutes)
http://youtu.be/D1aRSeT-mQE
Assignment
• OLS
– Online Part 1 – 6 questions
– Offline part 2 – 1 question
• Study Island
– Remember all 13 pathways are due.
– You need to have at least 10 questions in each
pathway.
– Earn a Blue Ribbon (75%+) and get extra credit